Hello!

What I want to do:
For using a Windows laptop as second screen for my KDE-powered PC I want to use a VNC client to connect to my PC (which acts as server), effectively turning the laptop screen into an extended screen for my PC this way.

What I need:
I need to create a virtual screen (not Desktop!). Basically like a second screen to the one I have plugged to my PC. The VNC will connect on this and make the illusion of an extended screen work.

What I tried:
xrandr with

• addmode (like here, also I have no VIRTUAL1; using an existing (disconnected) output did not work)
• setmonitor (like here)

It appears to me that KDE however ignores xrandr's configurations. I have been reading KScreen service might be the cause of it. I disabled it, though this has not proven to work either. KDE seems to always refuse applying any settings I do via xrandr.

So far all further searchmachine entries have not given me any more ideas on how to create a virtual screen in a KDE-compatible way.

My system:

• Fedora 34
• KDE Plasma 5.22.4
• KDE Framework 5.83.0
• Qt 5.15.2
• Kernel 5.13.5
• X11 (no Wayland)
• Mesa 21.1.5
• AMD GPU, RX 5700